Interesting. I would have expected that also - VxWorks (https://en.wikipedia.org/w/index.php?title=VxWorks&oldid=857084461 https://en.wikipedia.org/w/index.php

Interesting. I would have expected that also - VxWorks (https://en.wikipedia.org/w/index.php?title=VxWorks&oldid=857084461 https://en.wikipedia.org/w/index.php?title=VxWorks&oldid=857...) - Nucleus (https://en.wikipedia.org/w/index.php?title=Nucleus_RTOS&oldid=858384411 https://en.wikipedia.org/w/index.php?title=Nucleus_RTOS&oldi...) - perhaps ThreadX (the "spiritual successor of Nucleus") (https://en.wikipedia.org/w/index.php?title=ThreadX&oldid=852836528 https://en.wikipedia.org/w/index.php?title=ThreadX&oldid=852...) are on this list.